--- Makefile.orig	2013-01-23 19:59:16.000000000 +0000
+++ Makefile
@@ -91,17 +91,17 @@ distclean:
 install: install_lib install_docs
 
 install_lib: build_lib
-	mkdir -p $(PREFIX)/include/ahven
-	mkdir -p $(LIBDIR)/ahven
-	mkdir -p $(PREFIX)/lib/gnat
-	$(INSTALL) -m 644 $(SOURCES) $(PREFIX)/include/ahven
-	$(INSTALL) -m 444 $(ALI_FILES) $(LIBDIR)/ahven
-	$(INSTALL) -m 644 lib/$(STATIC_LIBRARY) $(LIBDIR)/ahven
-	$(INSTALL) -m 644 $(GPR_FILE) $(PREFIX)/lib/gnat
+	mkdir -p $(DESTDIR)$(PREFIX)/include/ahven
+	mkdir -p $(DESTDIR)$(PREFIX)/lib/ahven
+	mkdir -p $(DESTDIR)$(PREFIX)/lib/gnat
+	$(INSTALL) -m 644 $(SOURCES) $(DESTDIR)$(PREFIX)/include/ahven
+	$(INSTALL) -m 444 $(ALI_FILES) $(DESTDIR)$(PREFIX)/lib/ahven
+	$(INSTALL) -m 644 lib/$(STATIC_LIBRARY) $(DESTDIR)$(PREFIX)/lib/ahven
+	$(INSTALL) -m 644 $(GPR_FILE) $(DESTDIR)$(PREFIX)/lib/gnat
 
 install_docs: userguide
-	mkdir -p $(PREFIX)/share/doc/ahven
-	cp -r doc/manual/en/build/html $(PREFIX)/share/doc/ahven
+	mkdir -p $(DESTDIR)$(PREFIX)/share/doc/ahven
+	cp -r doc/manual/en/build/html $(DESTDIR)$(PREFIX)/share/doc/ahven
 
 check: build_tests
 	./tester -c
